The present invention relates to a method for finishing a surface of a work by electrolytic machining, and more particularly to a method for finishing the surface having a three-dimensional shape.
U.S. Pat. Nos. 3,527,686 and 3,607,689 disclose electrolytic machines. In the machine liquid electrolyte is continuously passed between an electrode and a work at a high speed during machining, so that residual products such as particles of eroded metal from the work, hydrogen gas, and others are discharged from the gap between the electrode and the work. However, in the case of the work having a complicated three-dimensional shaped recess, it is impossible to pass the liquid electrolyte through the gap having a complicated shape at a constant speed. The accuracy of the product is greatly influenced by the irregularities in the electrolyte flow. In addition, the concentration of the electrolyte at an outlet of an electrolyte tank is different from the concentration at an inlet, even if the pressure of the liquid is increased. Accordingly, it is impossible to produce accurate products.
Further, it has been found that the roughness of the surface of the product changes with the area of the surface. Accordingly, it is necessary to vary electric energy supplied between an electrode and a work in accordance with the area of the surface to be finished